From my experience the Phygelius when established will get a grip. I wanted to move mine but couldnt get it out and it is now spreading outwards and will be a huge clump eventually. The frost tends to damage it but it comes back stronger than ever. I definitely wouldnt move it to the front of a border. Height could be as high as 2 ft or more.

Hi, I think this was answered on question 25903

I have both the pink and yellow forms of Phygelius and they are both over 4ft tall. It responds well to pruning and comes back with more side shoots and is more vigorous. Give it a feed of tomato fertilizer and leave it where it is. It is evergreen in my garden and only needs a prune to tidy it up and nip off the frosted tips in spring.

Japanese anemone are invasive - you will need to restrict their root spread by some means - I usually dig them up in very early spring, or very late autumn (after flowering is finished, sometimes early winter) split and replant.
Phygelius too, once it gets going, is also horribly invasive, and quite difficult to dig out, but it must be done periodically or it will take over the whole garden. I really wish I'd used a root barrier round mine before planting it!